When a neutron star meets a gas cloud…

Scientists have now watched a neutron star run into a gas cloud spun off from …

This has got to be the oddest stellar couple I've ever read about. One half of the couple is a radio wave pulsar, a rapidly spinning neutron star. Its companion, which is only slightly more massive than the sun, rotates so quickly that it has flattened out from a sphere and created a belt of gas that it has spun off. The most amazing thing about the pair? Their orbits are such that twice every 3.4 years or so, the neutron star plunges through the gas belt.

During the most recent collision event, the European Space Agency was ready, and obtained data from both an orbiting observatory and ground-based instruments. Not surprisingly, the dive into a gas cloud upped the energy of the pulsar's emissions substantially, raising them out of the infrared and into the X-ray range. Still, the energy didn't match quite what was predicted based on models of pulsar-gas cloud collisions. Fortunately, with a fairly complete observational record of this star system, we should be in a much better position to understand what we're looking at in another three years, when this happens again. Since many pulsars form in the remains of supernovae that also create large gas clouds, it's thought that this understanding may have broader implications for stellar behavior.

While I'm out in space topic-wise, I'll mention that the Hubble group has released a new composite picture of the galaxy Messier 101, more commonly known as the pinwheel galaxy. A quick look at the image to the right should explain the nickname. By supplementing Hubble images with some from ground-based observatories, a composite was constructed at a whopping 16,000 by 12,000 pixels. Many lower resolution images are available, but the full resolution image seems to have been pulled since I looked this morning, presumably because of server strain. Even if someone begrudges the money spent on astronomy, I think we can view part of the Hubble investment as publicly funded art.